1. Field of the Invention
The present invention relates to a compact image reading apparatus and, more particularly, to a hand-held image reading apparatus.
2. Related Background Art
Conventional image reading apparatuses (to be referred to as image scanners hereinafter) are classified into sheet image scanners, for inserting a sheet and reading image data therefrom, and book image scanners, for reading image data from a sheet or a book placed on an original table by mechanically scanning a sensor.
It is, however, impossible to read image data from a very large sheet in the conventional image scanners. If an image scanner for reading a very large sheet is to be prepared, a very large sheet drive carrier or original table is required and a large number of sensors must be arranged, resulting in an expensive image scanner.
In order to solve this problem, a hand-held image scanner (i.e., a one-dimensional reader) has been used. However, the hand-held scanner must be moved accurately along a predetermined line, resulting in poor operability.
Another conventional image scanner is an X-Y image scanner which is moved in the X-Y plane to read two-dimensional image data. However, in this case, a matrix-line X-Y coordinate image must be prepared. The image scanner must read image data while detecting the matrix, thus also resulting in poor operability.